An all-anti conformation of the β-ala moiety in the crystalline state

Abstract

In marked contrast to the most favourable folded conformation, predicted from ab initio quantum mechanical calculations, the crystal structure analysis of the model system incorporating CONHCH2CH2CONH moiety, revealed the existence of an all-anti conformation, characterized by the backbone torsion angles: φ ≈ −146°, μ ≈ 172° and ψ ≈ 155°. Potential applications of the residue to form highly ordered, novel β-sheet like structure(s) with distinct faces have been suggested.